Given a sorted array A of size n and a number k, return the number of unique pairs which have a difference of k.

|arr[i] - arr[j]| = k where i < j

Example

A: [1, 3, 5, 7, 10]
k: 2
Answer: 3

A: [1, 3, 5, 7, 10]
k: 3
Answer: 1

A: [1, 3, 5, 7, 10]
k: 1
Answer: 0

Testing

Input Format

The first line contains an integer ‘T’ denoting the number of test cases.

For each test case, the input contains two lines:

• Two space-separated integers n and k.
• n space-separated integers denoting elements of the array A.

Output format

For each test-cases, the output is an integer denoting the number of k-diff pairs.

Sample Input

3
5 2
1 3 5 7 10
5 3
1 3 5 7 10
5 1
1 3 5 7 10

Expected Output

3
1
0

Constraints

1 <= T <= 100
1 <= n <= 104
0 <= k <= 105
1 <= Ai <= 105